Genetic polymorphism of CCND1 G870A and esophageal cancer susceptibility: A meta-analysis

The association between the polymorphism of cyclin D1 (CCND1) and esophageal carcinogenicity has been widely examined, however, it remains controversial. To evaluate the importance of CCND1 G870A polymorphism with regard to the risk of esophageal cancer, a meta-analysis was carried out that reviewed the available literature in order to clarify the controversies. This meta-analysis included 1,154 cases and 1,678 controls for CCND1 G870A polymorphism from seven published case-control studies. The odds ratio (OR) and 95% confidence interval (CI) were calculated using the Stata software version 11.1. The results were pooled using a dominant model to appropriately reflect a biological model of the genetic effect. No significant association was observed in the Caucasian (OR= 1.64; 95% CI, 0.84-3.20) or the Asian populations (OR = 1.30; 95% CI, 0.65-2.62), while no significant association was found in esophageal squamous cell carcinoma (ESCC) (OR=1.74; 95% CI, 0.79-3.81) or esophageal adenocarcinoma (EADC) (OR=1.18; 95% CI, 0.77-1.81). However, the comparison of A vs. G in CCND1 G870A showed significant differential susceptibility to esophageal cancer (OR=1.26; 95% CI, 1.00-1.59). These findings suggested that the CCND1 G870A polymorphism has no association with esophageal cancer risk in ethnicity and histology, respectively. Further studies are required to assess these associations in greater detail.